Rotary internal-combustion engine of the rotary abutment type



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ROTARY INTERNAL-COMBUSTION ENGINE OF THE ROTARY ABUTMENT TYPE Filed May 29, 1944 15 Sheets-Sheet 4 FIE-5o INVEN TOR.

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THE ROTARY ABUTMENT TYPE 15 Sheets-Sheet 6 Filed May 29, 1944 INVENTOR.

Aug. 24, 1948. F. BERRY 2,447,603

ROTARY INTERNA OMBUSTIGN ENGINE OF THE ROTA ABUTMENT TYPE Filed May 29, 1944 15 Sheets-Sheet 7 IN VHV TOR. M-g

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ROTARY INTERNAL-COMBUSTION ENGINE OF THE ROTARY ABUTMENT TYPE Filed May 29, 1944 15 Sheets-Sheet 8 IN V EN TOR.

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Aug. 24, 1948. F. BERRY 2,447,608

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ROTARY INTERNAL-COMBUSTION EN E OF THE ROTARY ABUTMENT 'I'YP Filed May 29, 1944 15 Sheets-Sheet 11 Aug. 24, 1948. F. BERRY 2,447,608

ROTARY INTERNAL-CQMBUSTION ENGINE CF THE RQTARY ABUTHENT TYPE Filed llay 29, 1944 15 Sheets$heet l2 fi l IN V EN TOR.

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Aug. 24, 1948. 2,447,608

F. BERRY ROTARY INTERNAL-COMBUSTION ENGINE OF THE ROTARY ABUTMEN'I' TYPE Filed May 29, 1944 15 Sheets-Sheet 14 IN VEN TOR.

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ROTARY INTERNAL-COMBUSTION ENGINE OF THE ROTARY ABUI'HENT TYPE Filed May 29, 1944 15 Sheets-Sheet l5 INVEN TOR. m

" zauum JTYQMTZ Patented Aug. 24, 1948 UNITED STATES PATENT OFFICE ROTARY INTERNAL-COMBUSTION ENGINE OI 'I'III ROTARY ABUI'MENT TYPE Frank Berry. Corinth. Bliss.

Application In! 29. 1!, Serial No. 537,907

The present invention relates to a rotary motor. consisting oi series rotary piston and rotary abutment combinations, which in the embodiment illustrated, consist oi sets oi iiring and compression rotors. the piston rotors being on a common shaft and the abutment rotors being on a series oi jack shafts. The piston rotors consist oi alternately arranged firing and compression rotors, coacting with firing and compression abutment rotors, and acting in such manner that fuel gas under compression by one set of coacting compression members is valve-passed to an adjacent set of co-acting firing members. via a pre-combustion chamber. Prior to firing. the latter chamber, in each case. is shut oil from the compression chamber by continued movement of the compression rotors. Firing is initiated in the appropriate pre-combustion chambers, and the fiaming gas enters the firing cylinders through ports in the appropriate firing abutment rotors. No valves are employed in these operations except those provided by the rotor elements themselves and consisting of ports formed in the abutment rotors and in the casing walls abutted by the latter rotors.

The piston and abutment rotors are oi special form. as hereinafter explained in detail, and the various objects of the invention will be hereinafter set forth. The primary object of the invention is to provide a high-speed rotary motor, capable of long periods of operation without repair, and which will develop high power with relatively low weight and bulk. At the same time assembly and disassembiy is iacilitated. Thus, by removing a head common to all of the rotors. together with removal or an accessory bracket, all of the abutment rotors. together with their bearings and shaft drive gear. may be removed as a unit, which action will expose the piston rotors and enable ready removal oi the detachable pistons therei'rom, or the replacement of compression sealing elements carried by the pistons, without removal of the pistons themselves. High efiiciency is secured with simple elements capable of long operation without derangement. as now to be described in connection with the accompanying drawing.

In the drawing:

Figure 1 is a view in elevation 01 a motor embodying the invention, the right hand portion being broken away at the lines AA.

Figure 2 is a view in elevation continuing and completing the right hand end of the motor.

Figure 3 is a plan view or the embodiment. the

2 right hand portion being broken away on the line 8-3.

Figure 4 is a plan view in elevation continuing and completing the right hand end of the motor.

Figure 5 is a view in elevation at the left hand end oi the motor, as seen irom the line H, Figure 1.

Figure 6 is a view in elevation at the right hand end or the motor, as seen from the line 6-4, Figure 4.

Figure 'l is a vertical section taken longitudinally through the motor, the latter being broken away at the line 0-8.

Figure 8 is a plan view of the structure shown in Figure '7. with the head removed, the view being in part a section on the line 8-8, Figure 1.

Figure 9 is a plan view of the structure shown in Figure 2 with the main head and bracket head removed.

Figure 10 is a vertical section on the line il-ib, Figure 7, showing the compression rotors at final compression position.

Figure 11 is a vertical section on the line li-l i, Figure 7, showing the combustion rotors at the instant oi firing.

Figure 12 is an enlarged fragmentary vertical section, showing the combustion rotors at the instant oi firing.

Figure 13 is a detail and fragmentary view showing the top area or one o! the combustion rotors and its piston, the pivoted piston seals having been removed.

Figure 14 is a plan view of the structure shown in the preceding figure.

Figure 15 is an enlarged fragmentary view showing the compression piston rotors at the position oi highest compression.

Figure 16 is a fragmentary view in elevation showing the top area of the compression piston rotor with its piston and pivoted seals in position.

Figure 17 is a plan view 01' the structure shown in Figure 16.

Figure 18 is an enlarged fragmentary view oi. one or the end casings, the view being in section, the section being through the removable head and the rotor shafts.

Figure 19 is a fragmentary plan view of one of the cast casing units, broken away at its top and exposing one-half or a combustion cylinder and a like section of a compression cylinder, parts of the motor head being shown.

Figure 20 is an elevation of the intake endor one or the compression abutment rotors.

Figure 21 is a vertical section taken longitu- 3 dinallyoisaidcompressimabimnentrotoron the line Il-Il, Figure ll.

Figureflisaviewinelevationotthedischarge end oi the compression abutment rotor.

Figurezllisaverticalsecflontsken through oneottbecmnbusticnabutmentrotorsonthe line II-II, Figure 26.

Figure 24 is a vertical section taken through a compression abutment rotor on the line 24-, Figure 21.

Figm-efiisanendelevaiionorthccombustion abutment rotor at the gas inlet end thereoi.

FigureZiiisaverflcal-angulatsectlononthe line II2I, Figure 25.

Figure 2'1 is a fragmentary section through one of therctoraillustratingaplstonsealintransverse section. together with its tension spring.

Figure28lsasectimalviewonthelineII-II, Figure 2'1.

Figure29isanisometricviewoi'thepistonseal which will hereinafter be termed the pivoted seal.

Figure3iiisaschematicviewshowinginluli anddottediinemeoitbecompression piston rotors and its abutment rotor in full compression, and (by dotted lines) the beginning of fuel intake. In this figure the hatched discs represent ports in the casing for the abutment rotor.

Figure 31 is a schematic view showing in cross section a combustion rotor pistm and its abutment rotor, and showing in curved outline the companion compression abutment and compression piston, certain ports being shown in full and inhatchedlinetoconstituteatiminggraph.

Flgilre32isaschematieviewshowlngacombustion rotor with its piston and the eo-acting combustion rotor. the valve ports of the latter being shown by hatched line. The figure shows by dotted line successive movements or the two rotors with various positims of the combustion abutment rotor ports, relatively to corresponding positions of the combustion rotor piston.

Flgure33isaschemaflcviewshowingthe outlines oi a compression piston rotor and co-acting compresion abutment rotor, showing in full lines the relative positions of the compression rotor piston and the com ression rotor abutment at the instant of firing in the companion combustion cylinder, dotted lines indicating other positlons.

Referring to the drawings it will be seen that the engine consists of a plurality of lower casings I, I, and I (Figures 1and2).whichcasingsare flanged and secured together by any suitable means, such as the bolts IX. Said casing sections may be roimded at their bases as shown in Figures and 6, and they will have flat top areas. Th topfacesofthecasines |,2,andIarebest shown in Figure 8. Rreierring to that figure it will be seen that in the present embodiment the abuttingareasoi'thecasingsaresotormedasto provide chambers. Each of these chambers receives an uppermost abutment rotor and an underlylng piston rotor oi greater diameter at the piston area thereof, as shown more particularly in Figures and 11. Here the abutment rotors consist oi two outermost combustion rotors ill. and two central compression abutment rotors l'l, as shown in Figure 8.

Form 01 the casinos Oomparisonotl'igures'landlllwillshowthe formation of intermediate casings of the structure, thue casings being indicated at 2. Each consists of a single casting, having a large intermediatewaterjacketatmlflgm'e'handlateral walls shaped to define one-halt oi a piston rotor chamber I. When the casings I are bolted together these rotor chambers are completed with the exception of those at the ends of the motor. The end sections are generally similar to the intermediate casings but each provides one-halt only of a rotor chamber, as shown in Figure 7, with reference to Figures 8 and 9. The water chambers Ix. and the flat top walls of casings i and 2 are formed with apertures, such as those indicated at I. for the passage 01' water or other cooling liquid.

As shown in Figure 'l the assembled castings l and I provide a central longitudinally extending shalt passageway, which receives a shaft I, having centrally disposed bearing members I and end bearings I, which may be of ball or roller WD The piston rotors As stated above, the outermost piston rotors are in combustion cylinders, heretofore termed rotor chambers, whereas. the two central piston rotors are in compression cyllnderswhich are larger than the combustion cylinders. All or the piston rotors are. alike in general construction and method of cooling. Each piston rotor has a hub directly mounted. on shaft I and keyed thereto, and the piston in each case is a separate hollow member as shown more particularly in Figures 12 to 17, inclusive. The combustion piston rotors are indicated at H, and the compression piston rotors are shown at II. The pistons for the combustion rotors are shown at ux. and the pisstons for the compression rotors are shown at IIX. Each piston is formed with a shouldered seat for receiving a heavy central threaded stud, which passes through an aperture at the seat and is threaded into the piston rotor, as shown in Figures 12 and 15, and two additional seats are provided for two additional studs "X, the central stud being indicated at II.

While the pistons of the combustion rotors have diflerent front and rear face contours than the compression pistons, the pistons are alike in other respects. They are flat walled at their sides. In each case the top of the piston is curved to conform with the curvature of the inner casing wall opposed to said top area 01 the piston. and pivoted seals are preferably employed for all oi the pistons.

The pivoted seals for the pistons The form or the pivoted seals for the pistons is best shown in Figures 27 and 29. Each seal consists of a plate-like member having a projected tapered bearing face at b, the pivoted seal itself being indicated at ll. Opposite the hearing face area the plate is formed with a rounded or bulbous base to be received in a corresponding aperture formed in a piston wall and to serve as a pivot. As indicated in Figure 27 the pivoted seals are inserted endwise into receiving apertures formed in the piston walls, which apertures include recesses (at ll, Figure 27) in which are placed springs it (Figure 28), which normally hold the pivoted seals with their tapered faces projected outwardly.

In the present embodiment three pivoted seals are employed for the bottom oi each side lace. three are employed for each top area 0! the individual piston, three for each side. and two for each side of the elongated and relatively narrow piston base which serves as an auxiliary piston, the function of which will later be described in detail. The said base, or supplemental piston,

ofthecombuetionrotorisindicatedat IIXZ. while that for the compression rotor is indicated at I!!! Theplacementofthepivotedsealsinanyone ofthepistonscanbeeflectedinsuchmanner thatthesealsaremutually engsgedsoastobe latched against displacement by mutual contact. This is done by inserting the top pivoted seals, thelengthofwhichissoproportionedthatthey are overlapped by the side pivoted seals, which in turn are overlapped by the bottom pivoted seals. The method of "overlapping such seals is somewhat schematically indicated in Figure 2'7. Itwillbenotedthatthehuboraxis endofthe seal II has been reduced to form clearance for a pin-like projection on the hub of the underlying seal b. Thus the hub of the underlying seal b will bar movement toward it of the overlying seal Thebdselomation olthepistom ByreferencetoFigure'iitwilibeseen that the base or supplemental mston area of piston III is relatively narrow so that the latter. for elective action, must have lateral contact bases throughout its circumferential path. At its upperpositio .asshowninl'igures l2 and 15,the lateral wall contact is provided by the opposed walls of the clearance opening in the abutment rotor. At all other points the said relatively narrow supplementary piston abuts opposed contact bases in: inwardly of the main rotor chambers I. The flat side walla and arcuate top wall ofeachmainpistonareawilllieincloserelationship to the inner walls of the rotor chambers with slip contact provided by the pivoted seals.

The abutment rotor:

The compression and combustion abutment rotors are alike in formation. The combustion abutment rotor is best shown in Figures 12, 25, and 26 and 117. It is formed with laterally proiected hub nx, formed with ring receivin grooves II. The sides of each combustion abutment rotor are flat and parallel, and between thewallsthere isextendedaweb ll,arcuatein form, and providing a face which moves in opposition to the top of the combustion piston with which the abutment operates.

Eachcastingorcasingmemberlatitstop will be formed for reception of the said abutment rotors and their bearings. Reference to Figure 26 will show that interiorly of the hub "X of each abutment rotor a hollow chamber is provided for flow of cool liquid. whichilow is guided by a baille II. All of the abutment rotors may initially be connected by hollow jack shafts ii in the manner illustrated in Figure 'l and these jack shafts are encircled by hearing rings 22 adapted to be received in seats at 2!. Figure 19. At opposite sides of these ring seats II, the top of each casing t is formed with channel ways at It to receive the rings on hub "X of the appropriate abutment rotor. The and easing I, likewise, are formed with a bearing seat and a single ring seat, as indicated in Figure l, with reference to Figures 8 and ii,

The drive for the combustion and compression rotors and for the abutment rotors As above described, the abutment rotors are connected by the hollow lack shafts ii. The left hand or initial abutment rotor receives in its left hand hub a hollow drive shaft ll carrying a spiral toothed pinion II in mesh with a spiral gearllontheiefthandendofshaft I. Shaft 1 has mounted thereon a worm II in mesh with a worm wheel II on a shaft 8|. This shaft leads to and drives an oil pump within a casing ll shown in Figure 1. This oil pump may be or any standard construction and its details are not illustrated.

The left hand end of the abutment shaft assembly, i. e., shaft II, carries a pulley 32 having a belt drive connection a. with a pulley 34 on a shaft leading to and operating water pump it (Figure 7). The right hand (Figure 9) member ll of the abutment shaft assembly carries a spiral gear I! in mesh with a gear (not shown) on the lower end of a distributor shaft. which end is supported by the walls of an aperture ax in a bracket ll. As indicated in Figure 6, and also Figure 2, the distributor itself is indicated at It, being controlled as to relative positions of contacts and distributor arm by movements of control lever II, as customary in such cases.

A suitable water pump is disposed in split housing II, and the pump is driven by shaft it (Figure 9). Shaft 3' is hollow and feeds into the water pump, the discharge duct of the water pump being indicated at 42.

The right hand end of the hollow piston shaft I assembly discharges into a water pump having a casing 43, Figures 9 and 2. The shaft projects outwardly of the water pump and carries a balance wheel 44 and the latter may be provided with a toothed ring Ii for connection with a starter.

Cooling liquid circulation A suitable radiator (not shown) will dlschange into a water pump or circulator 35, which has been hereinbefore mentioned. Referring to Figure 5, it will be noted that a vertical manifold it having a branch connection 41 is bolted to a bracket I, Figure I, the interior of connection ll communicating with the interior of the abutment shaft assembly. Manifold it is provided with a second branch 4!, likewise, bolted upon bracket It and communicating with the interior of shaft assembly I. In passing through the said shaft assemblies, heat is absorbed by the cooling liquid. and the hot liquid, hereinafter termed water, is drawn by water pump ll through discharge duct 42 into a conduit II, which likewise receives hot water drawn through hollow shaft assembly I by water pump 43, the latter discharging through a duct "X.

The motor head it is apertured for communication with a plurality of hollow risers 52 which, as shown in Figure 3, communicate with pipe I, so that by thermosyphon action the hot water from the cooling passages 21! and the hollow head ii, is drawn oil to aforesaid radiator (not shown), with which pipe I communicates. The cooled water from the radiator enters the motor casings through branch pipes 53, leading upwardly from pipe it, which will directly receive cool water from the radiator.

The oiling system At the right hand end casing I, a. gear box IX is amxed and it serves as a collection chamber for oil. At the left hand end of the motor, casing l serves for oil collection. The oil reaches these collection points as follows: pump 8| (Figure l) forces oil through pipe ll, through pressure filter it (Figure 1), and thence through a feed pipe ll mounted on top or the motor and having a plurality of branch pipes I. The said branch pipes lead downwardly through the motor head, through the intermediary of duct members It cast in the motor head. Seven of the said east ducts are shown in Figure 7. and as indicated in Figures 3 and 4, they will be increased in number for complete lubrication of the abutment rotors and their bearings. During the finishing of the motor head the said duct-like members II will be apertured by drilling through them as indicated by the dotted lines on Figure 7, and additional oil passage will be formed by diagonal drilled apertures as indicated at it.

The oil forced through ducts II will be brought under pressure in contact with the moving surfaces of the abutment rotors and their bearings. and duets I! will carry 01] downwardly from the hearings on the Jack shafts II to shaft I. The oil collected from shaft I will pass through apertures at X in the bottom wall of the casing shaft receiving aperture, for shaft I, said oil flowing into longitudinal passageways communieating with draw-off pipe ll, Figures 1 and 3, which feeds the oil pump. Pipe '8, likewise communicates with the gear box IX and left hand end casing I. so that when oil rises in these members it is drawn of! to feed the oil pump. Supplemental oil feed pipes will communicate with feed pipe 61. such as distributor oil feed pipe 51X, for feeding oil to various bearings and other rotating parts.

Cooling the piston rotors Reference to Figures 10 and 11 will show that the circulatory arrangement of the piston rotors is the same for both combustion and compression pistons; and. therefore, the same symbols will be used. The cool water drawn through hollow shaft 1 is given a circuitous path. It first strikes a plug p and is diverted through an angular duet at 6B (Figure 11). The diverted cooling liquid, as for example, water, will pass into the cooler side of the rotor piston and into cooling chamber c. It will then flow to chamber (1 and out through angular duct ii at the opposite side of the plug 9.

Cooling of the abutment rotors The water pumped through the jack shafts and accompanying end shafts, which are hollow as above described. passes into the hollow area of each abutment rotor, which hollow area contains the fln-like member III. This member, surrounded by the cooling water, increases the heat transfer from the abutment rotor and also effects turbulence in the water passing from one end of the abutment rotor assembly to the other end.

Intake of fuel gas to compressors Mounted on the engine head is a carburetor I. The discharge from the carburetor for the fuel mixture is indicated by dotted lines in Figure 10 at 82. It is a duet which communicates with a port 63 (Figure 10) for one of the compression cylinders, and a corresponding port for the adjacent compression cylinder. The suction passage of the fuel mixture into the compression area will be described with reference to the port 63 of Figure 10.

In Figure 10 fuel intake port 63 is closed by the flat wall face of the abutment rotor between the ends of a curved recess R (Figure 20) formed in the same side of the rotor, said curved recess extending, in this embodiment, about 252. The compression piston rotor and its eo-acting abutment rotor are. in the position of Figure 10. nearing the point of highest compression. The face of the abutment rotor for the compression cylin- 8 deroppositethathavingtboarcnate isprovidedwitharclativelylargefud port.whichilindicatedstfl. parisonofflglu'cslbandfl. endsoftberotorl'l,

willshorw tbelefthandoombusarcuate recessRoftheabuianantrotol-brinu portstlandilintotionandthecontinued movement of the piston ilx draws fuel gas into the compression cylinder by suction Whilstaprecedingchargeoffueigasisbeing compressed by the opposite face of the piston acting against the abutment rotor.

Such inward flow of the fuel gas is continued until Just before the piston III reaches the position of Figure 10.

Action 0] the combustion rotors When thechargeoffuelgasrecelvedbythe compression rotors has been forced by the compression piston through port ll of the compression abutment and into the on chamber Ii, continued movement of the abutment rotor ll closes port ll against the abutting casing wall. Prior to that time, and when port 54 is wide open to the chamber, intake ports N in the appr pr combustion aboutment rotor I" (Figure 11) come into r 818- ter with ports II in the adjacent easing wall (Figure 18) and communicating with the appropriate pre-combustion chamber. Priortotheopeningoiportsilthefueigas in the said chamber has been highly compressed therein and the cmnpression piston l'l isstillwhilethefuelgas is flowing through ports it, so that the ratio of compression is maintained and the volume is reased. When the ports 60 are wide open is initiated in the pro-combustion chamber, port I having closed. At this moment the relative positiom of the piston x, anditsabutmentareasshowninlflgureil. while compression piston II and its abutment are in the position of Figure 10.

The schematic graphs. Figures 30 to 33 rrinstothe raphofmgm'esoitwmhe seen that the positionoftherotors showninfulllinesisthatofl lgurelilandthat th yarenearingmaximum Itwill furtherbeseentbatthearclmteplsageltdoes not afford tion between the the! gas inlet ports it, I. when. however, the rotors have moved to the dotted line position, port II p d filrthcrslightoftbe abutment rotor will carry the arcuate passageway R. over port ii at which time gas will flow inward from the carburetor.

Figure 31 shows the corresponding time-positions of the compression and combustion rotors at time of firing. The combustion piston X, XX, and the abutment rotor I" are shown hatched and the compression piston "X and its abutment rotor II (as to the curved inner wall thereof) is shown in curved full lines. For clarity of illustration the combustion abutment rotor ports it are shown cross-hatched. The outlet port if of the compression abutment rotor is shown in full lines and the casing port leading from the compression cylinder to the combustion cylinder is indicated at 89. In the position of the members shown on the graph the ports Ii are wide open, and port 64 is out of communication with port if.

The graph Figure 32 is designed to show the combustion piston and its abutment rotor in three positions, i. e., (a) scavengingxb) start of fuel intalre, and (c) position of firing. In the position (a) the members are shown in dotted lines; in position (b) by dot and dash lines; and in position by full lines.

The purpose of the graph Figure 33 is to show the relative positions of the compression piston and its abutment rotor fuel discharge port at (a) the beginning and (b) the end of discharge of the compressed fuel gas. The caslngoiltlet port to the pre-combustion chamber is shown at il in hatched lines for clarity of illustration.

Firing The distributor 39 may be of conventional design having a rotor for two contact points leading to two conductors wires "X, "XX, and connected to the spark plugs 12, "X. The two cylinders are preferably fired 180 apart relatively to the respective positions of the combustion rotors.

The exhaust Each of the combustion cylinders is formed with an exhaust port 1|. Referring to Figure 11 it will be seen that the exhaust port communicates with an exhaust pipe X cast in the main casing. Each exhaust pipe communicates with the exhaust manifold II. The exhaust port Ill for each combustion cylinder is open at all times except when the combustion piston ilX moves over it. During the movement of the combustion piston from firing position, Figure 11, to the exhaust port, the piston acts to scavenge burnt gases remainin in the combustion chamber ahead of the piston. The burnt gases in the pre-combustion chamber are scavenged as follows. In the movement of the abutment rotor from firing position (Figure 11) the ports 86 are moved toward the exhaust port 10. When the piston llx approaches the exhaust port toward the end of a power impulse one of the ports '6' registers with one port 61' in the pre-combustion chamber at the time when the piston clearance passageway of the abutment is open to the cylinder and the burnt gases remaining in the pre-combustion chamber pass to the exhaust port II which may be under atmospheric pressure only. When both abutment ports '6' come into register with ports '1 of the pre-combustion chamber firing takes place, the position then is not quite that of Figure 11, because the timing is preferably so controlled that firing takes place before ports it are in complete register with ports 61 and when the fuel ases have not passed into the cylinder in sum- 10 cient volume to equalize pressures both immediaately back of the pistons and in the pre-combustion chamber.

It will be understood that various modifications may be made in the form and arrangement of the elements illustrated in the embodiment shown in the drawings. For example, the entire casing below its head, eliminating the ends, may be cast in one piece, the cylinders 5 may be round and the pistons conformed thereto, and any desired multiples of compressor and firing elements may be combined.

What I claim and desire to secure by Letters Patent is as follows:

1. In a rotary internal combustion motor having a casing, a compression chamber, a firing chamber adJacent thereto, piston and abutment rotors, a piston and a recessed abutment in each of said chambers, shafts for rotating said rotors, a duct for introducing gases into said compression chamber and for leading compressed gases from said compression chamber into said firing chamber, said shafts being operatively connected to rotate in unison, means for circulating cooling fluid around said chambers, and means for lubricating said rotors and shafts, the improvement which comprises a compression abutment arranged to provide a dwell communication between the compression chamber and its intake duct and a pre-combustion chamber formed in the casing between the compression and firing chambers, a duct for leading compressed gases into the same, and a duct controlled by the abutment rotor for leading compressed gases therefrom into said firing chamber, said pre-combustion chamber and the recessed portion of the abutment in the firing chamber and the piston rotor in the firing chamber all being in communication at the instant of firing.

2. A rotary internal combustion motor constructed in accordance with claim 1, in which the pistons are angularly related a number of degrees sufficient to cause the compression piston to reach maximum compression simultaneously with the firing piston reaching approximate firing position, communication between the precombustion chamber and the firing chamber being controlled by the abutment rotor.

3. In a rotary internal combustion motor having a casing, a compression chamber, a firing chamber adjacent thereto, piston and abutment rotors, a piston and an abutment in each of said chambers, a duct for introducing fuel gases into said compression chamber and duct means for leading compressed gases from said compression chamber into said firing chamber, said rotors being operatively connected to rotate in unison, means for circulating cooling fluid around said chambers, and means for lubricating said shafts and rotors, the improvement which comprises a compression abutment having a pair of disclike ends, a hemicylindrical wall between said disc-like ends. one of said ends being formed with a depressed channel adapted to provide a dwell communication between an intake port in the compression chamber wall and a second port spaced therefrom and leading to a fuel gas supply, and a fuel discharge port in the other of said ends.

4. In a rotary internal combustion motor having a casing, a compression chamber, a firing chamber adjacent thereto, piston and abutment rotors, a piston and an abutment in each of said chambers, a duct for introducing fuel gases into 

